Lighting fixture



March 23, 1943. w. 1.. SCHUMAKER 2,314,520

, LIGHTING FIXTURE Filed June 24, 1940 INVENTOR. Wax/4M Z Jaw/441mATTORNEY.

Patented Mar. 23, 1943 UNITED STATES PATENT OFFICE LIGHTING FIXTUREWilliam L. Schumaker, Milwaukee, Wis. vApplication June 24, 1940, SerialNo. 342,036

1 Claim. (Cl. 240-78) This invention relates to lighting'fixtures andparticularly to electric fixtures of the fluorescent type.

In fluorescent lighting, a mercury vapor arc confined in a cylindricaltube of glass constitutes the source of illumination, one or more ofsuch tubes being contained in a single fixture. These tubes areordinarily at least an inch in diameter and sometimes as much as fourfeet long, the light emanating in all directions from every point in theexternal surfaces thereof. Because of these characteristics, it isdifficult to control or direct the light rays to best advantage.

Fluorescent lighting fixtures ordinarily involve the use of reflectorswhich partially surround the luminous tube and direct the rays therefromin one general direction. When thus arranged, a substantial part of theentire light rays become trapped between the tube and the reflector andare lost. Also partial absorption in the extended reflecting surfacesordinarily employed is a further cause of reduced efliciency.

One object of the present invention is to provide in a fluorescentlighting fixture a novel combination and arrangement of parts by whichthe above losses may be materially reduced.

Another object is to provide in a fixture of the type mentioned a novelarrangement of reflectors by which half of the light rays emanat-' ingfrom each of a plurality of tubes may be directed in one generaldirection and the remainder in an opposite direction. 7

Another object is to provide a fixture having a plurality of verticallyspaced parallel luminous tubes combined in such manner that half of thelight rays from each of the tubes are directed laterally in onedirection and the remainder laterally in the opposite direction. Such afixture may be utilized to advantage as a central lighting fixture forstores and the like, the shelving and counters at opposite sides of thestore being illuminated by the oppositely directed rays.

Other objects and advantages will appear from the following descriptionof a fluorescent lighting fixture embodying the present invention.

In the accompanying drawing:

Figure l is a side elevation of a lighting fixture constructed inaccordance with the present invention.

Fig. 2 is a transverse sectional view on a larger scale takensubstantially along the line 22 of Fi 1.

Fig. 3 is a transverse sectional view of a lighting fixture embodyingthe present invention but of somewhat different form.

The fixture shown in Figs. 1 and 2 comprises an elongated frame having apair of vertical end heads I0 rigidly connected by a plurality ofelongated ho-llow sheet metal structures ll, [2 and I3 vertically spacedto admit the fluorescent tubes l4 therebetween. The connector structuresll, I2 and I3 and the tubes [4 extend horizontally and are substantiallyparallel. The tubes I4 are supported at opposite ends in conventionalterminal sockets carried by the end heads 10.

The upper connector structure H is fashioned to provide two horizontallyextended reflecting surfaces l5 and I6 which converge downwardly towardthe upper tube [4 and intersect in a horizontally extended edge lladjacent the tube. The intermediate connector structure I2 is alsofashioned to provide two horizontally extended reflecting surfaces I8and 19 which converge upwardly and. intersect in a horizontally extendededge 20 adjacent the upper tube 14. The edges I1 and 20 lie in a commonplane passing through the center of the upper tube l4 so that thereflecting surfaces I5 and I8 cooperate to direct toward the left all ofthe light rays emanating from one half of that tube, and the reflectingsurfaces I6 and I9 cooperate to direct toward the right all of the lightrays emanating from the other half of that tube.

The intermediate connector structure 12 is also provided withhorizontally extended downwardly convergent reflecting surfaces 2| and22 which cooperate in a similar manner with the lower tube l4 and withsimilar upwardly convergent reflecting surfaces 23 and 24 on the lowerstructure I3 to direct all of the light rays from one half of the lowertube M in one direction and all of the light rays from the other half ofthat tube in the opposite direction.

It will be noted that a very large portion of the light emanating, fromthe tubes l4 proceeds directly, without reflection, from the tubes, andthat the remaining small portions which proceed upwardly and downwardlyfrom those tubes are reflected outwardly by the relatively narrowsurfaces l5l6, Iii-l9, 2l22, and 2324, with the result that none of thelight rays are trapped and the loss due to absorption in the reflectingsurfaces is rendered to a In this instance two additional horizontallyspaced fluorescent tubes 25 are arranged adjacent the bottom of thelower connector structure [3, that structure being fashioned to providea pair of horizontally extended reflecting surfaces 26 and 21 whichconverge toward one of the tubes 25 and a similar pair of horizontallyextended reflecting surfaces 28 and 29 which converge toward the otherof the tubes 25, so that light is directed downwardly and laterally fromthe bottom of the fixture.

The several reflecting surfaces may be fiat, as indicated in Fig. 2, ormay be variously curved, the reflecting surfaces of the fixture shown inFig. 3 being curved concavely.

The fixture shown in Fig. 3 is otherwise somewhat similar to that ofFig. 2 except that only a single fluorescent tube 25' is provided at thebottom of the fixture and that tube is disposed directly below the twovertically spaced tubes M. of the tubes I4 is symmetrically disposedbetween a pair of downwardly convergent reflect-' ing surfaces l5 and[6' formed on the upper connector structure H and a pair of upwardlyconvergent reflecting surfaces l8 and I9 on'the intermediate structureI2; and the lower of the tubes I4 is likewise symmetrically disposedbetween a pair of downwardly convergent reflecting surfaces 2t and 22 onthe intermediate structure I2 and apair of upwardly convergentreflecting surfaces 23' and 24' on the lower structure 13'; so that allof the light from the left half of both tubes I4 is directed toward theleft and all of the light from the right half of As in the fixture shownin Fig, 2, the upper both of those tubes is directed toward the rightand no light rays are trapped or lost.

It will be noted that downwardly convergent reflecting surfaces and 3|provided on the lower connector l3 cooperate with the additional lowertube 25' to direct all of the light rays therefrom downwardly andlaterally in both directions.

Various changes may be made in either embodiment of the inventionhereinabove specifically described without departing from or sacrificingthe advantages of the invention as defined in the appended claim.

I claim:

In a lighting fixture the combination of a plurality of spacedsubstantially parallel fluorescent tubes so disposed that theirlongitudinal axes lie substantially within a common plane, two pairs oflight reflecting surfaces extending lengthwise of each of said tubes,each of said pairs of surfaces converging toward an adjacent tube andintersecting in a line disposed substantially within said plane,additional substantially parallel fluorescent tubes disposed at oppositesides of said plane, and'a pair of light reflecting surfaces extendinglengthwise of and adjacent each 'of said additional tubes, each of saidlast namedpair of surfaces converging toward the adjacent one of saidadditional tubes.

WILLIAM L. SCHUMAKER.

